1. Field of the Invention
The present invention relates generally to surgical instruments. More particularly, the invention concerns tissue retraction device that will fit within a small diameter trocar and will open or "fan out" once within the peritoneum.
2. Discussion of the Invention
During the performance of laparoscopic surgery, the surgeon will have occasion to retract tissue and other structures from the abdominal cavity. In the past, this has typically been accomplished using graspers and retractors of various sizes and designs. As a general rule, these prior art devices are relatively large and cumbersome to work with and, on occasion, can cause serious injury to the patient.
The apparatus of the present invention, provides for the first time, a very small, easy to use instrument which will conveniently fit within a trocar as small as five millimeters in diameter. The device can include one or more specially configured blades which can be extended outwardly once the blade is in position within the peritoneum.
In one form of the invention, a plurality of thin, resiliently deformable, pre-stressed blades are provided in a stacked relationship within an outer sleeve and are connected at their inboard ends to a support rod telescopically carried within the sleeve. The blades are pre-twisted about a stratigically located pivot point so that once the inboard end of the device is positioned within the peritoneum, the rod can be urged forwardly causing the end portions of the blades to automatically fan out in a manner such that the full width of the blades can be pressed against the tissue. By retracting the rod, the blades can be pulled into the sleeve and returned to their stacked and aligned configuration within the outer sleeve.